Gradually build your fitness by consistently running more miles and run 3+ days of the week. You should be able to run well under 45 minutes in your next 10km by being consistent in your training and running most of your training runs @ an pace. One day of the week run either 400m or 800m repeats or run a 2 to 4 mile tempo run @ 10km race pace. Weekly long run between 6 to 10 miles to work on endurance.

My last Bristol 10K was almost the same as yours in speed. The past 6 months, I've being trying to improve my pace dramatically as well. My strategy has been mainly treadmill-based - working out the speed in MPH for my target time, then running at or above that speed for as long as I can.

There will be far more sophisticated methods, but for me, with my limited training time... seemeed to work.

As others are saying Andrew it's Intervals for me that are the key for getting faster 5k / 10k times. Built up slowly of course in both speed and number of reps to prevent injury from the extra stresses of the faster pace. I would suggest something like 2 or 3 X 2 mile and 1 X 1 mile at 20 - 30 secs a mile quicker than your current 10 k pace and slightly faster for the mile rep with a 2 min jog recovery. This should start to make the current 10 k pace feel easier leading to improvement over the longer distance . These type of sessions seem to work for me when sharpening up for the ' shorter ' races